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Short term sound

What might cause a loud sound to come from the passanger side of the engine when you are in Drive or reverse but only occurs when the engine is cold and when you are at idle speed. Once you excelerate it goes away and after a couple miles of driving and the engine warming up it goes away.

“Loud sound” could describe an almost infinite number of noises.
Is it a tap, a bang, a clunk, a whine, a click, a screech, a hum, a buzz, a rattle, a …?

Is the noise continuous until warm-up, or do you only hear it once or twice before warm-up?

Do you have to accelerate gently for the noise to go away, or will even rapid acceleration cause the noise to disappear?

It sounds like a loud muffler would sound like. It is constant, no tap, bank or clunk. It start as soon as you shift and goes away as soon as you depress the pedel and accelorate. If you let off the gas you can hear it again until the car warms up. If in park or neutral you can rev the engine and hear nothing. Once the car/engine has warmed up (driving about 2-3 miles) you hear nothing even at idle.

bump

What year and how many miles on that Sedona? When was the last time you got all the recommended (as recommended in the Owner’s Manual) completed on your car? It could be as simple as lack of maintenance.

Joseph

Let us not forget that this is another one of our friend Indy’s vehicles that was purchased from a charity auction–just like his late Taurus with a bad head gasket. Do you remember how we helped him to nurse that dying vehicle along for many months?

Unfortunately, I suspect that this vehicle was not given optimum maintenance by its previous owner(s), and may now be suffering the consequences thereof. However, I could well be wrong.

The noise might be from a cracked exhaust manifold, or some other defect in the exhaust, but without being able to examine the engine and to hear it, I think that we are all just shooting in the dark. I really think that indy needs to park the vehicle at his trusted mechanic’s establishment overnight, and then allow the mechanic to listen to it in the AM when it is cold.

If the problem does relate to an exhaust issue, this could be a potential safety problem–especially in the winter when windows remain closed.

My present car is actually a used car purchase. Didn’t go auction this time, pickings were very slim. So bought a 2002 Kia sedona with 134000 miles for 3400. Overall the previous owner seemed to keep the van in good shape. I did have to put a new starter on but at 134,000 miles that is not to much out of the question. I would love to have the mechanic look at it, but not in the budget right now. I am just kinda amazed how a noise can be prevelent only when the car is first started and gone after a couple of miles and warmed up. I don’t think it’s an exhaust issue because wouldn’t you hear that noice when the engine was running? The noise only appears once the car is shifted into the Drive or Reverse position. In neutral or park you can rev the engine and you hear nothing but a good sounding engine.

So far just an oil change. Having the transmission flushed in late Dec and a new timing belt/serpentine belt replaceed in Feb. New air filter also put in when oil change was done.

If–as I am beginning to suspect–you have bad motor mounts and/or bad transmission mounts, when the engine is shifted into gear it is possible for the engine to move sufficiently to create a bigger gap in an already flawed exhaust manifold. Then, after the engine heats up, along with the exhaust manifold, heat expansion of the metal may allow the gap to get closed up enough so that the noise is not apparent.

When your budget allows, I suggest that you have the motor and trans mounts checked, along with the exhaust manifold. This is just a theory, but from a distance of several hundred miles, that is the best that I can come up with right now.

If it was the engine motor mounts woulnd’t the sound be happening as soon as i started the car? I can see it being transmission since it would impact the transmission until I shifted and put the transmission into action. How hard or easy is it to see if it is the mounts? How tough/expensive is it to fix that problem?